Kitchen-sized trash cans have it easy. You can buy bags with stretchy tops to fit snugly around the rim of the can. Smaller cans have to suffer through the indignity of ill-fitting trash bags that fall down inside the can, leaving you with a mess to clean up. But you can fix all that with a simple DIY cardboard insert.

Instructables user goland put together this cardboard insert that makes your trash bag fit snugly in whatever size can you build it for. You'll need a cardboard sheet that is nearly the height of your trash can and as wide as the circumference of the can. Goland notes that if the trashcan will fit inside a cardboard box, it's probably enough cardboard for the project. You'll need to fold the cardboard to fit the can, make a bottom, and some pull handles for your insert, and that's all there is to it. Hit up the Instructable for the step-by-step description.